Enantioselective catalytic 1,2-boronate rearrangements

A strategy that facilitates the construction of a wide variety of trisubstituted stereocenters through a catalytically accessed common chiral intermediate could prove highly enabling for the field of synthetic chemistry. We report the discovery of enantioselective, catalytic 1,2-boronate rearrangements for the synthesis of a-chloro pinacol boronic esters from readily available boronic esters and dichloromethane. The chiral building blocks produced in these reactions can undergo two sequential stereospecific elaborations to generate a wide assortment of trisubstituted stereocenters. The enantioselective reaction is catalyzed by a lithium-isothiourea-boronate complex, which is proposed to promote rearrangement through a dual-lithium-induced chloride abstraction orchestrated by Lewis basic functionality on the catalyst scaffold.

Automated summary

This study presents a strategy for constructing a wide variety of trisubstituted stereocenters through enantioselective, catalytic 1,2-boronate rearrangements. The chiral building blocks produced in these reactions can undergo two sequential stereospecific elaborations to generate a wide assortment of trisubstituted stereocenters. The enantioselective reaction is catalyzed by a lithium-isothiourea-boronate complex, which promotes rearrangement through a dual-lithium-induced chloride abstraction orchestrated by Lewis basic functionality on the catalyst scaffold.